Endless-chain bucket excavator.



G. L. HURsT. ENDLESS CHAIN BUCKET EXUAVATOR.

APPLIUATION FILED AUG. 28, 1906.

1 Patented Oct. 13, 1908.

GEORGE L. HURST, OF SAN FRANCISCO, CALIFORNIA.

ENDLESS-CHAIN BUCKET EXCAVATOR.

Specication of Letters Patent.

Application filed August 28, 1906.

Patented Oct. 13, 1908.

Serial No. 332,324

To all whom it may concern.' Y l Be it known that 1, GEORGE L. Hunsr, acitizen of the United States, residing in the city and county of SanFrancisco and State of California, have invented certain new and usefulImprovements in Endless-Chain Bucket Excavators, of which the followingis a specification. Y y

The present invention is more particularly designed for use inconnection with that type or class of dredging machinery known as "golddredgers or such dredgers as are used to cut the soil, elevate the same,and so treat the excavated and elevated soil as to remove therefrom suchprecious metal as may be carried thereby. In this class of machinery thesoil to be worked is ordinarily cut and elevated by means of an endlesschain bucket excavator, the cutting or freeing of the soil beingaccomplished through the medium of the elevating buckets, which bucketsare formed with a cutting lip for such purpose. The result of placingthe full cutting of the soil to be removed onto the buckets is tosubject the buckets and their connections to a considerable strain,requiring the buckets to be formed of extra strength to resist suchexcessive strains. As the entire cutting is erformed by the lip of thebuckets, it is o vious that the utility thereof is considerablyshortened.

The object of the hereinafter described invention is to relieve thebuckets of the initial cutting of the soil to be displaced, therebyremoving from the buckets the severe strains to which they haveheretofore been subjected, at the same time reducing the wear of thecutting lip of the bucket to a minimum, thus prolonging the life andusefulness of the buckets and increasing the Working efliciency of theexcavating mechanism.

To accomplish the above object, there is arranged between each bucket ofthe endless chain of buckets, one or more diggers or cuttinginstrumentalities, which serve to give an initial cutting to the soil soas to partially loosen the same immediately in Vadvance of and prior tobeing acted on by each bucket of the endless chain of buckets.

In order to comprehend the invention, reference should be had to theaccompanying sheet of drawings, wherein i Figure 1 is a side view of theswinging ladder of a dredging apparatus with the endless chain bucketelevator arranged thereon, the

position of the connecting links for the buckets, with the diggers'orcutting instrumentalities being shown, the ladder and the endless chainbucket elevator being partly broken away g4 Fig. 2 is a plan view of theparts disclosed in Fig. l of the drawings, and Fig. 3 is a detail viewof one of the connecting links removed, the digger or cuttinginstrumentality being secured thereto.

The numeral 1 is used to designate the ordinary swinging ladder of agold dredging apparatus, and 2 the buckets of the endless chain bucketelevator which is supported by and works over the said swinging ladder.The buckets 2 are connected by the members 3-3 of the connecting links,which connecting links and buckets 2 constitute the elevator of theendless chain bucket excavator.

The ends of the links are connected with the buckets by transverse pins10. The bucket 2 during the working of the dredger receives the materialto be worked, elevates the same and discharges the said material into asuitable device for receiving such excavated material. These featuresand the working thereof are well understood in the art of gold dredgers,and call for no detailed description herein.

To relieve the cutting lip 4 of the excavating bucket 2 of the excessivestrains and wear to which it is subjected, means are arranged in advanceof each bucket 2, for giving an initial cutting or loosening of the soilprior to the same being acted on by the excavating buckets, in fact, ifso desired, the hereinafter described cutting means may serve as thesole instrumentalities for releasing the soil to be removed, leaving thebuckets to act as the means for elevating the cut and loosened material.

In the present case, the means for cutting, digging and loosening thematerial to be elevated in advance of the buckets 2, comprisesprojecting plates 5-5, connected with the link members 3 3. These platesare mounted yon the link pins 6, and are held separated by the steelfillers 6. Between these projecting plates 5-5, which may more properlybe termed the digger plates, and near the outer end portion thereof, adigger or cutting blade 7 is clamped, the cutting point 7 thereofprojecting forwardly at an angle to the plates 5 5', so as to be inadvance of and in line with the travel of the bucket 2. Two such diggeror cutting instrumentalities are disclosed in advance of each of thesaid excavating buckets 2, although the number may be increased ordecreased at will.

The initial cutting or loosening of the soil is performed in advance ofthe buckets 2 by means of said diggers or cutting devices 7, thusrelieving the buckets of the heavy work of forcing loose the soil ascarried over the lower tumbler 8 of the swinging ladder 1, Fig. l of thedrawings. It will thus be observed that the work of cutting, digging,loosening or breaking up the soil t0 be removed, is distributed betweenthe initial cutting means and the buckets of the endless excavator, thusremoving from the buckets the severe strain to which they haveheretofore been subjected.

By the described means for disturbing the soil to be removed andelevated onto a gold dredger to be treated for recovering therefrom thevaluable metal carried thereby, the efficiency of the dredge is not onlyincreased, but the endless chain excavator works with greater freedomthan where the full cutting strain is placed on the buckets, and againthe wear on the buckets is reduced to a minimum, thus decreasing therepair work on the buckets, which is occasioned where the buckets arerequired to serve as the sole cutting means for the soil to bedisplaced.

Having thus described the invention, what is claimed as new and desiredto be protected by Letters Patent is- 1. An endless chain bucketexcavator and elevator, the same including a series of excavatingbuckets having cutting edges and a series of independent cutting deviceshaving cutting edges arranged to extend directly in advance of and atthe same depth as the cutting edge of each excavating bucket, and in thepath of travel of said cutting edges of the buckets.

2. An endless chain bucket excavator and elevator, the same including aseries of excavating buckets having cutting edges, a plurality of linksto connect the buckets, and a series of independent cutting devicessecured to the connecting links, said cutting devices having cuttingedges extending in advance of and at the same depth as the cutting edgesof the buckets, and directly in the path of the travel thereof.

3. In an endless bucket excavator, the combination with a series ofelevating buckets, of links for connecting the said series of buckets,of digger plates secured to and projecting from each link in advance ofthe buckets, and a digger or cutting device ses cured to and projectingfrom said digger plates so as to be in line with the travel of thebuckets, said cutting device releasing the soil to be removed prior tothe saine being acted on by the buckets.

4. An endless chain bucket excavator and elevator, the saine including aseries ol excavating buckets connected together and. having cuttingedges, and cutting devices provided with cutting edges arranged toextend in advance of and at the same depth as the cutting edges of thebuckets, and directly in the path of travel thereof.

5. An endless chain bucket excavator and elevator, the same including aseries of excavating buckets, a plurality of connecting links arrangedin pairs between adjacent buckets, a digger plate projecting from eachlink and a cutting blade clamped between each pair of digger plates.

6. An endless chain bucket excavator and. elevator, the same comprising`a series ol' independent excavating buckets, a series of linksconnecting a front end jmrtion ol' one bucket to the rear end portion ofan adjacent bucket, and a cutting device secured to each bucket link sothat the cutting edge thereof extends in advance of and at the sainedepth as the cutting edge of the bucket and in the path of travelthereof.

7. An endless chain bucket excavator and elevator, the same comprising aseries ol independent excavating buckets, a series of links connectingthe front end portion of one bucket to the rear end portion of anadjarcnt bucket, and a cutting device detachably secured to each bucketlink provided with a cutting edge extending immediately in advance ofand at the same depth as the cutting edge or lip of the bucket and inthe path of travel thereof.

8. An endless chain bucket excavator and elevator, the same including aseries ol` excavating buckets, a plurality of connecting links arranged.in pairs between adjacent buckets, a digger plate vprojecting from eachlink, a spacing member for each pair of links and a cutting bladeclamped between each pair of digger plates.

9. An endless chain bucket exmtvator and elevator, the same including aseries ollv excavating buckets having cutting edges and a. series ofindependent cutting devices having cutting edges arranged to extend inadvance of the cutting edge of each excavator bucket and at the samedepth as and directly in the path of travel of the cutting edges olIsaid buckets.

In testimony whereof I have signed my name to this specilieation in thepresence of two subscribing witnesses.

GEORGE L. llUllS'l itnesses:

JAMns MASON, HARRY D. Roonns.

'.l (it)

